Influence de la température et de la durée d'un traitement cryoprotecteur sur la résistance au froid de plantules de blé. Étude ultrastructurale des nucléoles des ébauches foliaires

1985 ◽  
Vol 63 (4) ◽  
pp. 663-671 ◽  
Author(s):  
Claude-Madeleine Gazeau
Keyword(s):  
Dimethyl Sulfoxide ◽  
Low Temperatures ◽  
Leaf Primordia ◽  
Distilled Water ◽  
Wheat Seedlings ◽  
Cryoprotective Agent

The nucleolus is sensitive to cold-protective media and to low temperatures. Nucleolar changes observed in the leaf primordia of wheat seedlings were related to the impregnation medium (distilled water or a mixture of glycerol, dimethyl sulfoxide, and sucrose), to the temperature (20 or 2 °C), and to the duration of the pretreatment (1 to 12 days). The cryoprotective agent generated the formation of nucleoli "with a diffuse granular zone." If the impregnation was done at 2 °C, characteristic nucleoli "with an indented aspect" occurred. The longer the duration of the impregnation and the more intense the subsequent freezing, the more important were the nucleolar changes. On rewarming the seedlings the various transformations were shown to be reversible.

Influence de la température et de la durée d'un traitement cryoprotecteur sur la résistance au froid de plantules de blé. Étude ultrastructurale des ébauches foliaires

1983 ◽  
Vol 61 (4) ◽  
pp. 1025-1039 ◽  
Author(s):  
C. M. Gazeau
Keyword(s):  
Endoplasmic Reticulum ◽  
Treatment Period ◽  
Day Treatment ◽  
Leaf Primordia ◽  
Ultrastructural Changes ◽  
Distilled Water ◽  
Wheat Seedlings ◽  
Starch Grains ◽  
Different Temperatures ◽  
Protective Treatment

Wheat seedlings were treated at different temperatures and for various periods of time with a cold-protective substance, composed of a mixture of glycerol, dimethylsulfoxide, and saccharose. When the treatment was done at 20 °C, slight ultrastructural changes appeared in leaf primordia as soon as day 1. Thus numbers of lipid globules increased significantly. When the treatment period was increased to 4 days, numbers of starch grains increased, and there was a marked enlargement of mitochondria and plasts. When the treatment was done at 2 °C, cytoplasmic alterations occurred later than at 20 °C. After a 4-day treatment, they were similar to changes induced at 20 °C. When the treatment period was increased to 12 days, dictyosomes were markedly altered. They clustered close to the nucleus in two or three groups and gave rise to numerous pale vesicles with various shapes and sizes. Around each cluster of such vesicles, there gathered many endoplasmic reticulum vesicles and other organelles (mitochondria, plasts, microbodies, vacuoles). A further cooling of 1 °C/min, down to −15 or −30 °C, enhanced these phenomena. After the seedlings were warmed up to 20 °C in distilled water, the changes induced by the frost-protective treatment and then by freezing were shown to be reversible. [Journal translation]

Accroissement de la résistance au froid de plantules de blé avec un milieu cryoprotecteur : variation de la température et de la durée du traitement d'imprégnation. Aspects physiologiques

1982 ◽  
Vol 60 (12) ◽  
pp. 2857-2863 ◽  
Author(s):  
C. M. Gazeau
Keyword(s):  
Dimethyl Sulfoxide ◽  
Freezing Tolerance ◽  
Low Temperatures ◽  
The Other ◽  
Ice Formation ◽  
Formation Temperature ◽  
Effective Protection ◽  
Wheat Seedlings ◽  
Other Hand

Different methods of hardening wheat seedlings to withstand freezing to low temperatures were studied. The procedures involved the impregnation of the seedlings with a cryoprotective mixture of glycerol, dimethyl sulfoxide and sucrose for various times and at various temperatures. Impregnation of the seedlings with such a mixture at 20 °C for 1 day imparted an effective protection to freezing at 1 °C/min. Longer periods of impregnation did not further increase the freezing survival. On the other hand, if the impregnation was carried out at 2 °C, freezing tolerance developed only slowly for the first 3 days, but improved rapidly between the 4th and the 6th day. Longer periods of impregnation at 2 °C did not further increase freezing survival. Freezing tolerance was observed to be related to both a lowered nucleation and ice-formation temperature in the impregnated tissues.

Diluted versus potentitized probes of silver nitrate (10e-2 to 10e-10) and wheat germination

2021 ◽  
Vol 15 (4) ◽  
pp. 22-23
Author(s):  
Corinne Kraus
Keyword(s):  
Silver Nitrate ◽  
Triticum Aestivum L ◽  
Distilled Water ◽  
Special Issue ◽  
High Dilution ◽  
Wheat Seedlings ◽  
Significant Difference ◽  
High Dilutions ◽  
Group A ◽  
Wheat Germination

Corinne Kraus, Ute Knobloch, Scherer Waltraud, Peter Christian Endler Interuniversity College for Health and Development Graz / Castle of Seggau, Austria Background In 1926, an influence of a homeopathically prepared high dilution of silver nitrate on the growth of coleoptiles of wheat seedlings was described (Kolisko 1926). Later, in an extensive series of experiments, wheat was observed under the influence of extremely diluted agitated silver nitrate (10e-23, “24x”). Stalk lengths clearly indicate that development is enhanced by the probe silver nitrate 24x as compared to control (Scherer et al. 2015). A preliminary experiment was performed in early autumn 2015 on stalk growth of wheat seedlings treated with (not potentized) dilutions of silver nitrate 10e-6 to 10e-10 (“6e to 10e”), compared to potentized silver nitrate 6x to 10x (N = 100 per group). A clear, albeit not statistically significant trend was observed of 6x-stalks being longer (23.4 + 16.2 mm) than 6e-stalks (13.0 + 10.9 mm). Objective The aim of this study was to investigate the influence of diluted versus potentized low dilutions of silver nitrate (10e-2 to 10e-10) on wheat germination. Method The experiments were performed in late autumn 2015 on wheat grain (Triticum aestivum L., Capo variety). The grains were observed under the influence of aqueous solutions 10-2 to 10-10 part per weight of silver nitrate, either diluted in steps of 1 : 10 in distilled water by mere pipetting (probes “2e – 10e”), or diluted and agitated in steps of 1:10 (to create potentized probes “2x – 10x”). Untreated distilled water (“w”) served as an additional control. All probes were applied blindly. 100 grains were observed per treatment group in each of the groups resulting a total of 2,000 grains. Grains were placed in glass dishes, probes were added and dishes were covered with lids and placed in drawers . The following endpoint criteria were defined: K1 = visible emergence of sprout material, K2 = lifting of the operculum and emergence of the sprout and W1 = development of three roots.   Result Germination rates K1 of seedlings treated with “w”-probes (blue), with “e”-probes ranging from 2e to 10e (black) and with “x”-probes ranging from 2x to 10x (red) at the measuring points 20h, 24h and 28h (from left to right for each of the probes). In K1, K2 and W, there is an obvious increase of germination rates from the high to the lower concentrations of silver nitrate, both in the “e” and in the “x”-groups and observable at 20h, 24h and 28h (p < 0.01). In contrast, germination rates of the two „w“-probes are practically alike (p > 0,05) When “e” and “x”-data are compared, germination rates are higher under the influence of “x” than under the influence of “e” (p < 0.01 for the pooled “x”-values compared to the pooled “e”-values with regard to K1 as well as K2 as well as W). Conclusion: A significant difference was found between wheat grains treated with mere dilutions compared to grains treated with potentised dilutions. References 1. Endler PC, Belavite P, Bonamin L,Jäger T, Mazon S. Replication of fundamental research models in ultra high dilutions 1994 and 2015 – update on a bibliometric study. Special issue Homeopathy London. 2015 a Oktober;104(4):234-45. 2. Endler PC, Schulte J, Stock-Schroeer B, Stephen S. Ultra high Dilution 1994 revisited 2015 – the state of follow-up research. Special issue Homeopathy London. 2015 b Oktober;104(4):223-6. 3. Kolisko L. Physiologischer Nachweis der Wirksamkeit kleinster Entitäten bei 7 Metallen – Wirkung von Licht und Pflanzen auf das Pflanzenwachstum. Dornach Schweiz: Philosophisch-Anthroposophischer Verlag am Goetheanum; 1926. 4. Kraus C, Knobloch U. Diluted versus diluted and agitated probes of silver nitrate (10-2 to 10-10) and wheat germination, Thesis (MSc); branch campus UCN at Interuniversity College Graz / Schloss Seggau; 2016. 5. Scherer-Pongratz W., Endler P.C., Lothaller H., Stephen S. Wheat and ultra high diluted silver nitrate – further experiments and re-analysis of data. Special issue Homeopathy London. 2015;104(4):246-9.

scholarly journals Spermatic abnormalities of piracanjuba Brycon orbignyanus (Valenciennes, 1849) after cryopreservation

2011 ◽  
Vol 71 (3) ◽  
pp. 693-699 ◽  
Author(s):  
JM. Galo ◽  
DP. Streit-Junior ◽  
RN. Sirol ◽  
RP. Ribeiro ◽  
M. Digmayer ◽  
...  
Keyword(s):  
Dimethyl Sulfoxide ◽  
Liquid Nitrogen ◽  
Distilled Water ◽  
Reproductive Characteristics ◽  
Fish Sperm ◽  
Before And After ◽  
Cryoprotectant Solution ◽  
Fresh Semen

The objective of this research was to verify the presence of spermatic abnormalities on semen of Brycon orbignyanus after cryopreservation. Semen was collected from ten four-year-old males who presented secondary reproductive characteristics for migrating fish. Sperm was evaluated for motility, vigor and spermatic morphology before and after cryopreservation. A cryoprotectant solution was made of 20 mL of yolk egg, 5.0 g of glucose and dimethyl sulfoxide diluted in distilled water (10 mL: 90 mL). The diluted semen (1:3, semen:solution) was submitted to nitrogen steam for 24 hours and then to liquid nitrogen (-196 ºC) for 60 days. Cryopreservation decreased the percentage of normal spermatozoa from 62.20% to 54.60%. Consequently, the percentage of spermatozoa with secondary abnormalities increased from 8.50% to 15.00%. However, there was no difference in primary abnormalities. Both spermatic motility and vigor were decreased in cryopreserved semen compared with fresh semen. In conclusion, cryopreservation of semen of B. orbignyanus increased the percentage of secondary abnormalities and decreased the spermatic motility and vigor.

Observations on bud formation and proliferations on cytokinin-treated root segments of Ophioglossum petiolatum

1969 ◽  
Vol 47 (10) ◽  
pp. 1579-1583 ◽  
Author(s):  
R. L. Peterson
Keyword(s):  
Apical Cell ◽  
Root Apex ◽  
Leaf Primordia ◽  
Distilled Water ◽  
Water Control ◽  
Cortical Cells ◽  
Root Segments ◽  
Low Concentrations ◽  
High Concentrations ◽  
Intact Root

Root segments of the fern Ophioglossum petiolatum with either an intact root apex or with the apex removed were treated with distilled water (control) or a range of concentrations of kinetin or benzyladenine in aqueous solution. Buds initiated on segments treated with distilled water or low concentrations of cytokinins had an apical meristem consisting of an apical cell with derivatives and a few leaf primordia located immediately beneath an air cavity formed by the lysis of cortical cells of the parent root. There was little cortical proliferation associated with the initiation of these buds. However, application of cytokinins at relatively high concentrations induced considerable proliferation of root tissue and a concomitant organization of numerous apical meristems in this tissue. Each induced meristem was structurally similar to those initiated on control root segments or those treated with low concentrations of cytokinins with the exception that leaf primordia were not as readily visible. Groups of tracheid-like cells were present in the callus-like outgrowths and, in root segments treated with 10.0 mg/l kinetin, large starch-filled parenchyma cells were evident at the periphery of the proliferations.

INVESTIGATIONS OF PERMEABILITY, DIAPAUSE, AND HATCHING IN THE EGGS OF THE MOSQUITO AEDES HEXODONTUS DYAR

1958 ◽  
Vol 36 (4) ◽  
pp. 541-554 ◽  
Author(s):  
W. E. Beckel
Keyword(s):  
Low Temperature ◽  
Sodium Hypochlorite ◽  
Water Loss ◽  
Low Temperatures ◽  
Room Temperature ◽  
Early Embryo ◽  
Adult Mosquito ◽  
Egg Cell ◽  
Distilled Water ◽  
Exposure To Cold

Methods for collection in the laboratory of many thousands of eggs from field-collected, blood-fed females are described. Also a way of separating fertile from infertile eggs is outlined. When the eggs are laid they are white but begin to darken within one-half hour. The darkening did not occur when the egg cell or early embryo was killed.Two changes in permeability in the prediapause stage of the eggs of Aedcs hexodontus were observed. The first took place as the chorion changed from white to black. The egg lost and gained water easily when first laid but resisted water loss and uptake as the chorion darkened. However, a complete waterproofing did not result. With the formation of the transparent cuticle a further change in permeability occurred. The egg lost hardly any water even when exposed to extreme desiccation and what little water was lost was regained very slowly. However, the cuticle, with the chorion removed in sodium hypochlorite, was quite permeable. The impermeability of the chorion and cuticle combination must result from the bonding between the two and this bonding must be disrupted by the dechorionation.To study the obligate diapause that occurs in the late embryogeny of the mosquito egg the effect of making water available to the embryo, of light, and of low temperature was studied. Diapause was not broken when water was available to the embryo, nor did alternate periods of light and dark at room temperature or at lower temperatures disrupt the diapause. To test the influence of cold the temperature of 1° and −3 °C. were used to simulate the temperatures in the field. The low temperatures were found to terminate the diapause but the numbers of eggs hatching did not steadily increase with an increase in the time of exposure to cold. No clue has as yet been discovered to explain these results. A hatching infusion of decaying adult mosquito bodies in distilled water was found to give more hatching than did distilled water alone. The mechanism of the hatching stimulus is not known.

Scanty integration of osteochondral allografts cryopreserved at low temperatures with dimethyl sulfoxide

2010 ◽  
Vol 19 (7) ◽  
pp. 1184-1191 ◽  
Author(s):  
Francisco Forriol ◽  
Umile Giuseppe Longo ◽  
Eduardo Alvarez ◽  
Stefano Campi ◽  
Purificacion Ripalda ◽  
...  
Keyword(s):  
Dimethyl Sulfoxide ◽  
Low Temperatures ◽  
Osteochondral Allografts

scholarly journals Preservation of Avian Cells at Sub-zero Temperatures

1979 ◽  
Vol 32 (5) ◽  
pp. 475 ◽  
Author(s):  
N Ratnamohan ◽  
PB Spradbrow
Keyword(s):  
Dimethyl Sulfoxide ◽  
Cryoprotective Agent ◽  
Cryoprotective Agents ◽  
Long Term Storage ◽  
Low Concentrations ◽  
Short And Long Term ◽  
Term Storage

The cryoprotective agents dimethyl sulfoxide (DMSO), glycerol, polyvinylpyrrolidone (PVP) and dextran were evaluated for their ability to protect avian cells during storage at sub-zero temperatures. DMSO was the most effective cryoprotective agent for the short- and long-term storage of avian cells and glycerol was also effective when used at low concentrations. PVP and dextran did not protect avian cells during storage in our experiments. Primary chicken cells and avian cells at higher passage levels were successfully recovered after storage with DMSO for periods ranging from 4 to 12 months.

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